Technology for smoothly starting an internal combustion engine is already known, as disclosed, for example, in JP 2011-47348. According to this technology, when a request is made to start an internal combustion engine, cranking is performed by a cranking motor. Further, if the speed of the internal combustion engine becomes greater than a resonance band of the vehicle, injection of fuel to the internal combustion engine and ignition are started. Thereby, the occurrence of vibrations when starting the internal combustion engine is suppressed.